A typical internal combustion engine includes a main cooling circuit configured to allow coolant, such as water, to flow through a radiator. A bypass conduit opens during a start phase of the engine and allows the coolant to circulate through the bypass conduit. In general, a thermostatic valve system controls the flow of coolant. At least one valve is driven by a thermally expansive member and fit with a bypass valve. The valves are connected to each other such that, at a predefined lower temperature, the thermostatic valve is closed and the bypass valve is open. As the temperature increases, the thermostatic valve opens, and the bypass valve gradually closes. WO2010/061343, entitled “A Cooling System For A Combustion Engine,” which is hereby incorporated by reference in its entirety, provides further details of a cooling system.
Certain valves may include a metering feature that allows smaller amounts of fluid to be metered therethrough. However, many of the metering features are sized and shaped so as to allow too much fluid to pass therethrough. In short, the metering features may be too large to allow for smaller or finer-tuned amounts of fluid to pass therethrough. Further, known metering features may be formed with complex shapes and boundaries, which may add time and cost to manufacturing.